The Uni-Ball Gel refills that I've purchased are thankfully available in the 1.0 mm impression, which makes for a bold signature and gives my notes maximum clarity. By loading up on the refills, I avoid shelling out for the full Uni 207 Impact pens, because the refills make it possible for me to use, over and over again, my favorite type of sturdy pen. I'm a writer who must autograph books, and I've recommended the Uni 207 to other writers who have followed my advice. I'll be sure to tell them about the refills.